Keeping the brain active and stimulated throughout life can prevent the build up of amyloid plaque associated with Alzheimer's disease. People who regularly challenge their brains by reading, writing and playing stimulating games have lower levels of amyloid plaque than those who do not, a study by Susan Landau of UC Berkeley's Helen Wills Neuroscience Institute suggests. Although several other research projects have shown a link between physical and mental activity and the development of Alzheimer's disease, this is the first to use amyloid PET imaging to show the lower levels of deposits. "In completely healthy older people about a third of them have amyloid, [but are] healthy [with] no memory problems," she said. "The thinking is that they're probably at much higher risk than normal people without [amyloid deposits]." Today (January 26th), the Alzheimer's Society and Alzheimer's Research UK urged the government to improve dementia research. Find out about dementia care and support services at Barchester care homes.